With that, let's talk about two notechart-related terms that have been associated with the idol production franchise in Taiko history.im@s Notecharts
This term seems to have been deprecated and wasn't too widely used to begin with, but it is recorded with major fan communities like wikihouse, so here's a brief run down anyway.

Also called the Angel Dream Notechart (エンドリ譜面), the im@s Notechart (アイマス譜面) is one that has rather basic patterns, mostly a simple mix of single notes and triple 16th cluster at a 1/8 spacing, but mainly challenges Donder in processing notechart patterns under high speed and/or density conditions.

Again, the use of this term is limited, and as the rise of this next category, the term has appeared to be replaced in meaning.

Call Notecharts
Definitely not to be confused with a telephone call or a (margin) call in the financial fields, call (コール) is the encouraging display of vocal shouts and cries during a sports event or contemporary concerts, or basically like cheering in English.

In Idolm@ster (and some other idol game franchises), there are recognized patterns of calls specific and in time to each song in the franchise. Calls have been present in both the games and other derivative media like the anime and, of course, live concerts.

As an example, take a look at this excerpt from the Idolm@ster (main series) anime, where the idol girls from 765 Production puts on a concert performance of Jibun REST@ART (自分REST@ART), and the audience calls on enthusiastically in time with the song. This video specifically is also annotated with the lyrics and most major call cues, being a "call training video" and all.

Now check out the same song on Taiko no Tatsujin Murasaki ver., especially the Futsuu notechart (4★). Can you see the resemblance? And here is where we draw the definition: a Call Notechart (コール譜面) is a notechart that has a lot of the recognized call patterns worked into the notes.

With more and more Call Notecharts propping up like THE IDOLM@STER (new chart) and Majide...!?, Some of the common patterns start to emerge, including:

Usually large notes and sometimes sped up immensely for excited calls

Very easy sections consisting of yellow drumrolls and single notes (like the PPPH call), that is unfitting for higher difficulty

Very short bursts of Go-go Time, with the firework effects emulating stage effects in an idol live event

Part of the introduction of Call Notecharts also involved massively revamping some of the previously included songs. This has caused resentment from Donders who feels nostalgia with the old notecharts. As such, the Taiko Team went and readded older Oni notecharts as Ura notecharts whenever they can, including updates to AC0, repackaging newer 3DS2 DLCs, and a free DLC patch to V Version's default im@s song.